It is common practice to utilize a centrifugal braking mechanism to control the maximum speed of a spool or wheel as it rotates due to externally applied forces. One issue with this technique is the inability to slow the spool or drum at the end of the desired rotating period while external forces are still being applied.
Centrifugal brakes provide torque based on the speed of the rotating drum, spool, or wheel. A centrifugal brake cannot stop a rotating object in motion while external forces are providing a torque larger than that of the centrifugal brake. In the instance of a spool paying out line, as the end of the line wrapped on the spool approaches, the centrifugal brake cannot bring the spool to a stop.
What is needed, therefore, are techniques for a braking system that can apply a linear braking force proportional to the speed of the rotating spool and that can stop a rotating object while external forces are still being applied.